Dental facing



y 1927' T. E. DIMELOW DENTAL FACING Filed Jan. 14. 1926 V2.6 fitter/Mega l witness Patented July 5, 19 27.

UNITED. STAT 1,634,612 ES PATENT OFFICE.

THOMAS E. DIMIELOW, 0F PHILADELPHIA, PENNSYLVANIA, AS SIGNOR TO JOHN MCKINNON, 0F YORK, PENNSYLVANIA. I

DENTAL FACING.

Application filed January 14, 1926: SerialNo. 81,284

The invention relates to improvements in artificial teeth of the general type shown by my U. S. Patents No. 947,378 and No. 1,070,785. in which a porcelain facing is provided in its lingual side with a socket to receive a projecting pin on a backing with which said lingual side contacts. Experience has taught that the pin has a tendency to split the facing, under the continual strain of mastication, as each thrust'placed upon the facing-causes tight forc-ingagainst the pin of the side of the ward the occlusal end of said facing. It is the object of the present invention, therefore, to provide a new ad improved con struction in which all thrusts placed on the aforesaid socketside, are transmitted to the solid portions of the facing at opposite sides of the port-ion which is weakened by the socket.

lVith the foregoing in view, the invention resides in the novel subject matter hereinafter described and claimed, the description being supplemented by the accompanying drawing.

Figure 1 is an inner side elevation of the improved facing and the backing, showing the strain transmitting means in dotted lines.

Figure 2 is a vertical sectional view as indicated by line 22 of Fig. 1.

Figure 3 is a view similar to Fig. 2 but illustrating a different form of construction.

Figure 4: is a sectional view as indicated by line 4-4 of Fig. 3. I

Figure 5 is a perspective view of the form of reinforcing and strain transmitting member shown in Figs. 3 and 4.

Figure 6 is an edge view showing a still further form of reinforcing and strain transmitting member.

In the drawing above briefly described, the numeral 7 designates a backing plate whose outer side is provided with at least one rigidly attached projecting pin, aplurality of these pins being preferably employed, as indicated by the numerals 8. These pins, as in the patents above referred to. converge with the backing 7 in a direc tion away from the occlusal edge of the latter and while this construction is preferable, it. is possible that good results could be obtained with other angular relations 0f backing and pin or pins.

The. minimal delgnates the artificial socket or here tobore.

tooth or facing, whose lingual side is intended to contact with the buccal side of the backing-'7, said facing havinga socketor bot-e110 for each pin 8, the pin or pins being suitably cemented in the socket or sockets.

y preference, each pin is formednear its free end, with a peripheral groove 11 to per.- mit more effective anchoring by the cement.

lVhen an artificial tooth of'the type: above described, is in use, each thrust placed upon the tooth or facing 9, during a process of mastication, causes the side ofthe socket or bore 10, toward the cclusalcn'd of the facing, to thrust forcibly against the pin 8, the result being that'there is quite a forcible tendency tofsplit' the facing. To overcome this di'l'licult-y, I have provided the improvement now to be described.

The. form of construction shown in Figs. 1: and. 2 will be first explained. In these views, 12" designates an elongated. reinforcing and strain-transmitting member whose intermediate portion 13 is positioned between the socket or bore 10 and the occlusal end of the facing 9, said intermediate portion being exposed at the interior of said socket or bore, at the side of the latter toward said occlusal end. The end portions or armsof the member 12 extend in substantially a labio-gingival direction from the socket or bore 10, diverge toward the vertical edges of the facing, and are em bedded in the solid portions of the tooth or facing, at opposite sides of the central portion, which is weakened by said socket or Each thrust upon the facing, is re ceived by the intermediate portion 13 of the member 12, and by this member is transmitted to solid portions of the facing which are well capable of withstanding the strain and thus the danger of splitting the facing is effectively overcome.

The member 12 is by preference of substantially U-shape and it 'maybe formed with openings 14: or may be otherwise constructed to permit effective anchorage in the facing or tooth. While this member is its intermediate portion 13 is in the form of a sleeve-like lining for the socket or bore of the facing. The lining 13 may be of any desired length, from a mere ring to quite an elongated tube and it may either be continuous circumferentially, or may be split. In Fig. (i, a lining portion 13" is shown on a reinforcing and straintransmitting member 12 said lining portion being split.

It will be seen from the foregoing that a distinct improvement has been produced, over the subject matter shown by the prior art, and it will be understood that I am not restricted to. exact details which I have selected for illustration in the present application.

It may be added, that when a sleeve or the-like is provided at the intermediate portion of the reinforcing and strain-transmitting member, it serves effectively to hold said member in proper place while the porcelain facing is being molded around it. This construction has also been found to be of advantage in properly locating and spacing the sockets of the facing, so that a backing prepared for use with any facing, is also usable with any other facing. Obviously, the invention may be used in con nection with an artificial tooth of any desired size and shape, to replace any natural tooth 1n the dental arch.

1. An lmprovement in a dental facing of the type whose lingual side 1S adapted to vcontact With a backing; said facing being formed with a bore which extends labio-occlusally from said lingual side and is open at its lingual end only to receive a backingcarried pin; said improvement comprising a relatively long and narrow ti -shaped metal strip which is embedded in the facing in a plane at substantially right angles to the axis of said bore, the intermediate portion of said U-shaped stripv being disposed at the side of the bore toward the occlusal end of the facing while the arms of said strip extend from the bore in substantially a labio-gingival direction but also diverge to points near the vertical edges of the facmg.

2. A structure as specified in claim 1; together with a metal sleeve connected to and extending transversely of said interme diate portion of the U-shaped strip, said sleeve being co-axial with and forming a lining for said bore.

In testimony whereof I have hereunto affixed my signature.

Thomas E. DIMELOW. 

